Humidifier

ABSTRACT

A humidifier for attachment to an air duct or plenum chamber including novel rotor means for introducing water into the air flow in the duct or plenum. The rotor includes a plurality of spaced apart circular disks formed of performated sheet material which are maintained in axially spaced apart relation on a rotor shaft by a series of annual spacer blocks. Water absorbption pads formed of open celled plastic material are secured to one side face of each of the disks for the purpose of picking up of water from a pan-like supply housing for delivery into moving the air flow in the duct.

United States Patent 1 62 62 62 62 62 62 62 62 62 62 62 76 /75' /6 /Z5 (70 (76 H0 [70 H0 70 70 Bracich 1 May 15, 1973 [54] HUMIDIFIER FOREIGN PATENTS OR APPLICATIONS [751 lnvenw Lmis Bmich, Y 278,118 10 1927 Great Britain ..261/92 73 Assignee; N i Humidifier Corporation, 930,226 7/1963 Great Britain. ..26l/92 Rosemont, Ill. Primary Examiner-Dennis E. Talbert Jr. 22 Fld: A .31971 1 1e Att0rneyRichard D. Mason et a]. [2]] Appl. No.: 168,546

[57] ABSTRACT [52] US. Cl. ..26l/92, 55/%Z,/?(/}23l25, A humidifier for attachment to an air duct or plenum chamber including novel rotor means for introducing [5l] InLCl ..F24i 3/14, BOld 47/18 water into the air flow in the duct or plenum The [58] Field of Search ..26l/83, 84, 90, 9|,

261/92 94 99 107 DIG l5 DIG rotor includes a plurality of spaced apart circular disks 23 0 2 3 1 232, formed of performated Shet material are maintained in axially spaced apart relation on a rotor shaft [56] References (m d by a series of annual spacer blocks. Water absorbption pads formed of open celled plastic material are UNITED STATES PATENTS secured to one side face of each of the disks for the R26,243 8/1967 Hotchkiss et al. ..261/28 p rp e of picking up of water from a pan-like supply 1,843,202 3/1932 housing for delivery into moving the air flow in the 2,210,354 8/1940 duct, 3,309,021 3/1967 7 Claims, 5 Drawing Figures HUMIDIFIER The present invention relates to a new and improved humidifier for attachment to the bottom wall of a hot air duct or plenum chamber, and more particularly the present invention is directed to a humidifier having new and improved rotor means for picking up water from a pan-like supply housing for discharge into the hot air flowing within a duct or plenum chamber.

Accordingly, it is an object of the present invention to provide a new and improved humidifier suitable for attachment to an air duct or plenum chamber for humidifing the air flow therein.

Another object of the present invention is to provide a new and improved humidifier of the character described, having novel rotor means for supplying the necessary humidification water to the air flowing in a duct or plenum chamber.

Another object of the present invention is to provide a new and improved rotor assembly for a humidifier which rotor efficiently provides a maximed transfer of water into the air flowing in the duct with a minimum amount of corrosion and a minimum accumulation of salts and other materials in the rotor and adjacent areas.

Another object of the present invention is to provide a new and improved humidifier of the character described which has improved resistance against corrosion and which is easily cleaned.

Another object of the present invention is to provide a new and improved humidifier of the character described which is low in cost, reliable and efficient in operation, easy to install on existing duct work or plenum chambers, and which is low in operating expense.

These and other objects and advantages of the present invention are accomplished in an illustrated embodiment which a humidifier adapted for attachment beneath an opening or cut out in the bottom wall of an air duct or plenum chamber. The humidifier includes fan means for holding a supply of water for humidifing the air flowing through the duct or plenum and a shaft is supported for rotation in the pan beneath the opening. Rotor means is mounted for rotation in the fan and a portion extends downwardly into the water in the pan while another portion extends upwardly through the duct wall opening to deliver moisture to the air flow in the duct.

The rotor means confuses the plurality of circular disks of perforated sheet material, spaced apart axially on the shaft by a plurality of annual spacers.

Water absorbption pads, formed of open celled plastic material are secured to one side of each disk for lifting water from said pan means into said air duct for pick up by the air passing between the pads and adjacent disks. Water is also picked up on the back of the pads through the perforation in the disks to afford excellent transfer of moisture into the air flow.

For better understanding of the present invention reference should be made had to the following detailed description taken into conjunction with the drawings in which:

FIG. 1 is a transverse vertical cross section through a duct or plenum chamber showing a humidifier constructed in accordance withthe features of the present invention installed thereon for humidifing the air flow in the duct.

FIG. '2 is a horizontal, sectional view taken substantally along lines 2 of FIG. 1 looking downwardly on the humidifier.

FIG. 3 is a transverse, vertical, sectional view taken through the humidifier substantally along the lines 3 of FIG. 1.

FIG. 4 is a transverse, sectional, view taken substantally along lines 4-4 of FIG. 1..

FIG. 5, is an exploded, perspective view, showing construction details of the novel rotor means of the humidifier.

Referring now more specifically to the drawings, therein is illustrated a new and improved humidifier constructed in accordance with the features of the present invention and referred to generally to the reference numeral 10.

The Humidifier 10 is adapted to be secured beneath an opening 12 formed in a bottom, horizontal wall 14 of a duct or plenum chamber 16, in which hot air is flowing generally in the direction of the arrows A" in FIG. 2.'The air flow contained in the duct or plenum chamber 16 is adapted to be moisten by the addition or humidified water supplied from the humidifier 10 and for this purpose the humidifier includes a pan-like supply housing 20, preferably formed of transparent molded plastic material so that the upper level of the water as well as the condition of the rotor assembly and other components of the humidifier may be visually asertained. In order to facilitate attachment and support of the humidifier beneath the opening or cut out 12 in the wall 14 of the duct or plenum 16, the pan or housing 20 has a horizontal edge flange 22 integrally formed around the upper peripheral edge of the open upper end. The upper edge flange 22 is adapted to be I secured to the inside of a downardly facing recess formed in a rectangular frame member 24 which is secured in place on the bottom wall 14 of the duct or plenum around the cut out or opening 12 by suitable sheet metal fastening means 30.

The rectangular frame 24 provides a stiffening function around the around the opening 12 in the bottom wall of the duct and a suitable ceiling gasket 26 is sandwiched between the duct wall and the upper surface of the frame as best shown in FIG. I and 3. The humidifier pan 20 is detachably supported from the frame 24 and is held in place by a plurality of wing nuts which are treaded on to downardly projecting studs or fasteners 30 carried by the frame.

The humidifier is readily attached or detached from the duct or plenum by loosening the wing nuts and when humidifier is not in use, the opening 12 in the duct is closed by a cover plate (not shown) which is seated within the recess formed in the frame 24.

As best shown in FIG. 1, 2, and 4 the water supply pan 20 is fored with a filling chamber 32 at one end of substantally reduced cross sectional area. The filling chamber projects outwardly of the side of the duct or plenum 16 (as shown in FIGS. 1 and 2) and is supplied with water through a conduit 34, the outlet of which is controlled by a float controled valve mechanism indicated as 36. The float controlled valve mechanism maintains a relatively constant upper or underfilling level of water in the pan 20 to insure that underfilling or overfilling does not occur. However, a skillway passage 48 (FIG. 4) is provided in a side wall of the filling chamber overflow of water into the duct should the float control valve fail.

At the opposite end of the pan 20 there is provided an integrally formed motor housing section 40 in which it is mounted an electric drive motor 42 having a cooling fan blade 44 carried on lower end of the armature shaft 46 of the motor. This shaft extends upwardly to drive a gear reduction assembly 48 for rotating the rotor assembly of the humidifier at a low speed.

The gear reduction assembly and drive motor are supported from the walls of the housing 40 by suitable fasteners 49, and the gear box includes a right angle, horizontal output shaft 50 having a drive nut 52 on the outer end thereof which is adapted to receive a flatted end 54a of an elongated rotor shaft 54. The rotor shaft supported in the pan 20 for rotation about a horizontal axis directly below the rectangular opening 12 in the lower duct wall 14. The outer end of the rotor shaft is supported in a U-bracket 56 (FIGS. 1 and 4) which bracket is attached to the outer end wall of the water inlet chamber 32. The inner end of the shaft 54 extends through an opening 55, (FIG. 1) in an end wall of the pan 20, so that the shaft 54 is detachably engageable with the drive nut 52 on the gear reducer output shaft.

In accordance with the present invention'the humidifier includes a novel rotor assembly generally indicated by the reference number 60 and comprising a plurality of parallel, spaced apart circular disks 62 formed of perforated sheet material such as aluminum or stainless steel. The rotor shaft 54 is formed with an elongated flat portion 54b which is dimensioned to fit central apertures 62a provided in each of the disks in order to form a keyed connection between the shaft and the disks of the rotor assembly.

Parallel spacing between the disks axially along the shaft is maintained by a plurality annular spacers 64 formed of non-corrosive material such as plastic or the like. The spacers and disks are slipped on to the shaft one after another until the desired length is obtained and the spacers maintain the spacing between the disks. As viewed in Flg. l the disk 62 at the right hand end of the rotor isseated in position at the end of the shaft section 54b and a spacer 64 of reduced thickness may be provided on the right hand side of the disk to provide support for the end disk at right angles to the shaft.

The thin space Bellville" 64 is maintained in contacts against the right hand side of the disk by means of a Bellville" type spring washer 66. Similar construction is provided the left hand end the rotor structure and a left hand spring washer 66 exerts spring pressure against all of the intermediate disks and spacers on the shaft between opposite ends of the rotor assembly.

In accordance with the present invention, at least one side face of each performated disk 62 is provided with a moisture absorption pad 70 of substantial thickness formed of open-celled plastic material such as polyurethane foam or the like. As the absorption pads 70 are rotated, a lower portion thereof is continuously dipped into the water container in the pan for pick up of the water in the open celled structure thereof. The mositure picked up is carried upwardly upon rotation into the duct of the disks and direct exposure of the moistened pad to the hot air flowing in the duct or plenum 16 takes place.

The hot air in the duct flows between the parallel disks 62 absorbs or picks up water or moisture from the absorption pads 70. The open cell structure of the plastic absorption pads is capable of holding a high volume of water and is extremely efficient delivery of water to the air flow from exposed side faces in the duct. Water transfer to the air flow is effected via the back faces of the pads which cemeted to the structurally supporting perforated disks through the performation therein.

Each absorption paid is able to deliver moisture to the air flow in the duct from both sides thereof owing to the larger area of the perforations in the circular supporting disks 62. The thickness of the open-celled plastic pads is approximately 25-30 percent of the axial spacing distance between adjacent pairs of support disks 62 on the rotor shaft 54. This provision provides for a minimum of friction loss upon air passage over the moving rotor assembly and for a maximum pickup or transfer of moisture from the absorption pads into the air flow.

The pads are cemeted to the perforated disks 62 in a manner whereby the cement is supplied to cover only the solid portion of the disks and accordingly little if any cement is present in the areas adjacent the perforations in the disks so that water is freely absorbed by the air flow through the holes or perforations.

In this manner, the perforated disks provide structure for supporting the resilient moisture pads 70 and yet do not materially detract the the transfer of water and moisture from the paid to the air on the supported side of the pad because of the relatively large area of the perforations in the disks, as best show in FIG. 3. Preferably the average cell size of the absorptive pads 70 is controlled so the average cell is approximately one-half the size of the perforations of the disks 62. This achieves a znaximum rate of transfer of moisture into and out 0 he pad while providing good pad life.

The humidifier is readily cleaned and should it become clogged or plugged with salts or scale caused by evaportion of the water, the unit is easily detached from the duct simply by the loosely the wing nuts 28 and lowering the pan 20 downwardly from the duct or plenum 16. The water supply pan 20 is also provided with a removable drain plug 72 so that drainage of the water can be provided without removing the unit from the duct. Moreover, should difficulty with the float control assembly 36 be encountered, the valve may be readily reached for service simply by removing a cover plate 74 on the laterally offset, water supply chamber 32, which plate is normally held in place by cap screws 76.

After the humidifier is removed, or detached from the duct or plenum, the rotor assembly 60 may be easily removed, and one or more disks pads or spacers can be easily removed, and one or more disks, pads or spacers can be easily cleaned or replaced. After the cover plate 74 is removed, the shaft and the rotor assembly as a unit is removable by withdrawal upwardly from the pan. The flatten end of 54a of the shaft is decoupled from the drive nut 52 and the inner end portion of the shaft 54 is withdrawn through the opening 55, which opening is above the water level. The right hand of the shaft 54 is lifted upwardly out of the support bracket 56 and once the rotor assembly is removed from the pan 20 the spring washers 66 are loosened and the disks, pads and spacers may be removed and cleaned or replaced.

From the foregoing it will be seen that the the present invention provides a new and improved humidifers having a novel rotor assembly which provides for a maximum humidification rates for the air flowing through a duct or plenum with a minimum of service problems and a minimum of water waste and operational cost.

I claim:

1. A humidifier for attachment below an opening in the bottom wall of an air duct comprising pan means for holding a supply of water for humidifying the air flowing in said duct, a shaft supported for rotation in said pan means beneath said opening and rotor means carried for rotation with said shaft extending into said duct through said opening and into the water in said pan means, said rotor means including a plurality of spaced apart, circular disks of perforated sheet material, a plurality of spacers on said shaft between adjacent disks for maintaining selected axial spacing therebetween, and a water absorption paid formed of open celled plasticmaterial carried on one side of each disk for lifting water from said pan means into said air duct for introduction into the air flow therein.

2. The humidifier of claim 1 wherein said absorption pads are of substantial thickness which is less than the spacing between adjacent disks to permit passage of air between an outer face of a pad and the facing surface of the next adjacent perforated disk.

3. The humidifier of claim 1 including key means for locking said disks and shaft to rotate together.

4. The humidifier of claim ll wherein each paid is adhesively secured to a perforated disk and they are of each pad covering the perforations in the disk are substantially free of adhesive to permit passage of air and water into said pad through said perforations.

5. The humidifier of claim 4 wherein said pads are formed from open celled polyurethane foam sheet materials having a thickness of about 25 percent of the spacing interval between disks.

6. The humidifier of claim 4 wherein theperforations in said disks are approximately double the size of the average cell in said absorption pads.

7. The humidifier of claim 6 wherein said pan means is formed of transparent plastic material and including means for regulating the upper level of water supplied to said pan means below said shaft.

it l 

1. A humidifier for attachment below an opening in the bottom wall of an air duct comprising pan means for holding a supply of water for humidifying the air flowing in said duct, a shaft supported for rotation in said pan means beneath said opening and rotor means carried for rotation with said shaft extending into said duct through said opening and into the water in said pan means, said rotor means including a plurality of spaced apart, circular disks of perforated sheet material, a plurality of spacers on said shaft between adjacent disks for maintaining selected axial spacing therebetween, and a water absorption paid formed of open celled plastic material carried on one side of each disk for lifting water from said pan means into said air duct for introduction into the air flow therein.
 2. The humidifier of claim 1 wherein said absorption pads are of substantial thickness which is less than the spacing between adjacent disks to permit passage of air between an outer face of a pad and the facing surface of the next adjacent perForated disk.
 3. The humidifier of claim 1 including key means for locking said disks and shaft to rotate together.
 4. The humidifier of claim 1 wherein each paid is adhesively secured to a perforated disk and they are of each pad covering the perforations in the disk are substantially free of adhesive to permit passage of air and water into said pad through said perforations.
 5. The humidifier of claim 4 wherein said pads are formed from open celled polyurethane foam sheet materials having a thickness of about 25 percent of the spacing interval between disks.
 6. The humidifier of claim 4 wherein the perforations in said disks are approximately double the size of the average cell in said absorption pads.
 7. The humidifier of claim 6 wherein said pan means is formed of transparent plastic material and including means for regulating the upper level of water supplied to said pan means below said shaft. 